[TowerTalk] Re: Antenna element vibration damping - How

[mcduffie at actcom.net]

On Sun, 10 Aug 2003 11:15:31 -0400, N2TK, Tony wrote:

> Hi Steve. I agree Force 12 design helps. But at WP2Z, all day long you can
> see the element tips vibrate from even a light updraft at the edge of the
> steep slope. This is especially apparent with the 10m elements. Going to try
> adding rope inside the element tips to see if it helps

The sort of vibration that rope helps to reduce is not something you
can see.  It is a high frequency vibration, not a wiggling in the
breeze.  You might effect the lower frequency vibration or bouncing
with rope just because of the added weight changing mechanical
resonance.  But the real use of rope is for higher frequency
vibration that gets absorbed by the rope floating free on the inside
of the element.  It works similar to the lead-weight Stockbridge
dampers used on power lines and guy wires.  Google "stockbridge
damper" for more info.

Gary

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